Role of Occiput Spinal Angle-A Novel Sonographic Index to predict the outcome of labour
Introduction: The attitude (relationship of head of a fetus to the cervical spine) in the first stage of labour has a significant impact on the outcome of labour. Deflexion of the fetal head is determined by digital vaginal examination during labour. However, different ultra-sonographic indexes have been developed to predict labour outcomes. Occiput spine angle (OSA) is a novel ultra-sonographic marker which can be used to predict operative delivery.
Objective: To determine the effect of the occipital spinal angle measured through transabdominal ultrasound during the first stage of labour on the labour outcome.
Materials and Methods: This prospective cross-sectional study was carried out at Department of Obstetrics and Gynecology Unit 2, Holy Family Hospital, Rawalpindi from June 2020 to Dec 2020 which included 380 low-risk pregnant women in the first active stage of labour. Occipital-spine angle (OSA) was defined as the angle formed by the fetal occiput and the cervical spine on the sagittal plane at the transabdominal ultrasound. For each case, the angle was calculated twice and independently by the 2 radiologists who were unaware of labour outcome to minimize intra and inter-observer error. Data were analyzed using SPSS version 23.0. P-value ≤ 0.05 was considered significant.
Results: Incidence of operative delivery was 17.2%. A cut-off value of 1260125.50 of OSA had a sensitivity of 92.3% and specificity of 98.1% to predict operative delivery. Binary Logistic Regression showed that gestational age, OSA, and Head station are significant with the OR= 1.15, 0.711, and 0.32 respectively.
Conclusion: OSA is a good predictor of operative delivery at a cut-off value of 1260. It should be determined at routine ultrasound booking during pregnancy. More studies should be conducted to highlight its importance.
2. Betrán AP, Ye J, Moller AB, Zhang J, Gülmezoglu AM, Torloni MR. The increasing trend in caesarean section rates: global, regional and national estimates: 1990-2014. PloS one. 2016; 11(2). https://doi.org/10.1371/journal.pone.0148343.
3. Gupta M, Garg V. The rate and indications of caesarean section in a tertiary care hospital at Jaipur, India. Int J Reprod Contracept Obstet Gynecol. 2017 Apr 27; 6(5):1786-92. DOI: http://dx.doi.org/10.18203/2320-1770.ijrcog20171530.
4. Eide KT, Morken NH, Bærøe K. Maternal reasons for requesting planned cesarean section in Norway: a qualitative study. BMC pregnancy and childbirth. 2019 Dec; 19(1):102. https://doi.org/10.1186/s12884-019-2250-6.
5. American College of Obstetricians and Gynecologists. Dystocia and augmentation of labor. Practice Bulletin No. 49, December 2003, Reaffirmed 2013. DOI: 10.1016/j.obstetgynecol.2003.10.011.
6. Cunningham FG, Leveno KJ, Bloom SL, et al. Abnormal labor. In: Cunningham FG, Williams JW, editors. William’s obstetrics. 24th ed. New York, (NY):McGraw-Hill; 2014. Chapter 23.p.455–472. https://accessmedicine.mhmedical.com/content.aspx?bookid=1918§ionid=185051261.
7. Kumar P, Dhaka M, Gaur SS, Pant R, Banerjee KP. Study the assessment of risk factor for primary caesarean section in multigravida. International Journal of Medical and Biomedical Studies. 2020 Jan 2; 4(1).
8. Rénes L, Barka N, Gyurkovits Z, Paulik E, Németh G, Orvos H. Predictors of caesarean section– a cross-sectional study in Hungary. The Journal of Maternal-Fetal & Neonatal Medicine. 2018 Feb 1; 31(3):320-4.
9. Rabei NH, El‐Helaly AM, Farag AH, El‐Naggar AK, Etman MK, El‐Moteily MM. Intrapartum fetal head circumference and estimated fetal weight as predictors of operative delivery. International Journal of Gynecology & Obstetrics. 2017 Apr; 137(1):34-9.
10. Kasbaoui S, Séverac F, Aïssi G, Gaudineau A, Lecointre L, Akladios C, Favre R, Langer B, Sananès N. Predicting the difficulty of operative vaginal delivery by ultrasound measurement of fetal head station. American journal of obstetrics and gynecology. 2017 May 1; 216(5):507-e1.
11. Dall'Asta A, Angeli L, Masturzo B, Volpe N, Schera GBL, Di Pasquo E, Girlando F, Attini R, Menato G, Frusca T, Ghi T. Prediction of spontaneous vaginal delivery in nulliparous women with a prolonged second stage of labor: the value of intrapartum ultrasound. Am J Obstet Gynecol. 2019 Dec;221(6):642.e1-642.e13. doi: 10.1016/j.ajog.2019.09.045. Epub 2019 Oct 4. PMID: 31589867.
12. Hehir MP, Burke N, Burke G, Turner MJ, Breathnach FM, Mcauliffe FM, Morrison JJ, Dornan S, Higgins J, Cotter A, Geary MP. Sonographic markers of fetal adiposity and risk of Cesarean delivery. Ultrasound in Obstetrics & Gynecology. 2019 Sep;54(3):338-43.
13. Ghi T, Maroni E, Youssef A, et al. Intrapartum threedimensional ultrasonographic imaging of face presentations: report of two cases. Ultrasound Obstet Gynecol. 2012;40:117–118.
14. Akmal S, Kametas N, Tsoi E, et al. Comparison of transvaginal digital examination with intrapartum sonography to determine fetal head position before instrumental delivery. Ultrasound Obstet Gynecol. 2003;21:437–440
15. Ghi T, Bellussi F, Azzarone C, Krsmanovic J, Franchi L, Youssef A, Lenzi J, Fantini MP, Frusca T, Pilu G. The "occiput-spine angle": a new sonographic index of fetal head deflexion during the first stage of labor. Am J Obstet Gynecol. 2016 Jul;215(1):84.e1-7. doi: 10.1016/j.ajog.2016.02.020. Epub 2016 Feb
16. Hamilton BE, Martin JA, Osterman MJK, Driscoll AK, Rossen LM: Births: provisional data for 2016. National Vital Statistics Rapid Release June 2017, Report No. 002.
17. Wise, J., 2018. Alarming global rise in caesarean births, figures show. BMJ, p.k4319.
18. World Health Organization and Human Reproduction Programme: WHO Statement on CaesareanWHO/RHR/15.02.http://www.who.int/reproductivehealth/publications/maternal_perinatal_healt h/cs-statement/en/. Accessed 20 Mar 2018.
19. Murphy DJ, Liebling RE, Verity L, Swingler R, Patel R. Early maternal and neonatal morbidity associated with operative delivery in second stage of labour: a cohort study. The Lancet. 2001 Oct 13;358(9289):1203-7.
20. Khalid MA, Ghani R, Khalid MF et al. Association of delivery procedure with APGAR scores among neonates born to healthy Pakistani mothers: a pilot study [version 1; peer review: awaiting peer review]. F1000Research 2018, 7:346.
21. Maged AM, Soliman EM, Abdel latif AA, Nabil M, Said OI, Mohesen MN, Raslan AN, Elbaradie SM. Measurement of the fetal occiput-spine angle during the first stage of labor as predictor of the progress and outcome of labor. The Journal of Maternal-Fetal & Neonatal Medicine. 2019 Jul 18;32(14):2332-7. DOI: 10.1080/14767058.2018.1432589
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